WASHINGTON — The budget President Obama unveiled Tuesday would raise more than $1 trillion over 10 years through changes in the tax code by closing loopholes, raising some taxes and cracking down on enforcement.

But the budget also cuts taxes for some taxpayers, most notably an expansion of the Earned Income Tax Credit for 13.5 million low-income Americans beginning in 2018.

Obama's budget contains 175 different revenue proposals, of which 28 are new in this year's budget.

Among them:

• Expanding the Earned Income Tax Credit for workers without children. Currently, workers without qualifying children can claim the credit if they're ages 25 to 65 and make less than $14,790. Obama's proposal would expand the age range from 21 to 67 and the income limit for individuals up to $18,070 for individual taxpayers. The proposal would save taxpayers $59.7 billion over 10 years.

• Making owners of professional services firms pay a greater share of payroll taxes. Some sole proprietors, for example, take only a portion of their income as salary and the rest as corporate profits, allowing them to avoid Social Security and Medicare taxes. The proposal would raise $37.8 billion over 10 years.

• Excluding college Pell grants from income taxes, saving taxpayers $8.9 billion over 10 years. The proposal would expand eligibility for educational tax credits by not counting Pell grants as income.

Obama would boost collections by regulating tax preparers, increasing the enforcement budget by 7% and requiring more electronic filing.

The proposed tax changes are part of Obama's insistence that deficit reduction come through both spending cuts and increased revenue. "The budget secures that revenue through tax reform that reduces inefficient and unfair tax breaks and ensures that everyone, from Main Street to Wall Street, is paying their fair share," Obama said in his budget message to Congress.

Obama's budget comes the week after the Republican chairman of Congress' chief tax-writing committee released his own draft legislation to overhaul the tax code.

The two proposals are very different: Obama's budget would make the tax code more progressive, reducing taxes on low-income workers and increasing them on the wealthy. Rep. Dave Camp's proposal keeps the same basic distribution of tax burden across income groups.

But there are a few areas of general agreement. Both contain a new tax on banks, though they would calculate those taxes differently. Camp's would raise $86 billion over 10 years. Obama's "financial crisis responsibility fee" would raise $56 billion.

"Unfortunately, the president's budget adds more complexity to the tax code and increases taxes for more Washington spending," Camp said in a statement. "That is the wrong direction."

The competing visions for overhauling taxes will collide on Capitol Hill on Thursday when Treasury Secretary Jacob Lew testifies before the House Ways and Means Committee, which Camp chairs.